Latch control device



July 2, 1968 KUCHLER 3,390,910

LATCH CONTROL DEVICE Filed Sept. 1, 1966 2 Sheets-Sheet 1 96 INVENTOR ABRAHAM AUCHLER 36 5e; av

54 5 MAHOA/EY&/'/0R4/BAKE2 46 ArroeA/srs July 2, 1968 A. KUCHLER LATCH CONTROL DEVICE 2 Sheets-Sheet 2 Filed Sept. 1, 1966 FIG-i6. 96

I wvsuroe ABRAHAM KucHLE/e a MA HONEY 8: HOENBAKER A TTOENEYS United States Patent 3,390,910 LATCH CONTROL DEVICE Abraham Kuchler, Anaheim, Calif., assignor to Emhart Corporation, Bloomfield, Conn, a corporation of Connecticut Filed Sept. 1, 1966, Ser. No. 576,657 13 Claims. (Cl. 292-359) This invention relates to a latch control device and more particularly, to a latch control device which, when formed as a part of a lock set includes a unique spring arrangement therein for retaining a locking member in each of its locking and unlocking positions retaining a latch actuating spindle locked stationary or permitting rotation of said spindle for actuating the latch. Even more particularly, this invention relates to a latch control device which may be of the foregoing type and in which said unique spring arrangement therein also simultaneously serves as self-alignment means for the latch actuator spindle which resiliently returns said spindle to a center or neutral position after rotation of said spindle in either direction of rotation to actuate the latch, or in the alternative, said latch control device may be formed with said unique spring arrangement serving solely as said latch actuating spindle self-aligning means.

Certain of the prior latch control devices for operating door latches, such as that described and shown in the prior Unetic United States Letters Patent No. 2,998,273, issued Aug. 29, 1961, have included interior and exterior rotatable doorknobs operatively connected through a latch actuating spindle to a latch mechanism mounted in the door, said latch mechanism having a latch member normally resiliently urged to a doorframe strike engaging position and movable to a retracted position disengaged from said strike upon rotation of either of said doorknobs in either direction of rotation. Further, a spindle retainer housing is secured on the latch actuating spindle rotatable with said spindle, and said housing encloses a radially slidable locking member which may be selectively moved between an extended locking position engaging a stationary frame of the latch control device and locking said spindle and doorknobs against latch operating rotation, and a nonlocking retracted position disengaged from said stationary frame and permitting rotation of said doorknobs for operating said latch. The movement of the locking member between said locking and nonlocking positions is accomplished through cam means on an auxiliary locking spindle extending within the latch actuating spindle and controlled by a selectively pivotal button at the interior doorknob and usually a lock at the exterior doorknob.

The particular rotative positioning of the auxiliary locking spindle to place the locking member in one of its locking or nonlocking positions is controlled by a detent or retainer slide mounted in association with said auxiliary locking spindle and cam connected thereto. The retainer slide is constantly resiliently urged toward the locking spindle, normally resiliently retaining through the cam connection said locking spindle in one or the other of its positions. The resilient urging of the retainer slide, however, permits radial outward movement of said slide to permit the rotative movement of said auxiliary locking spindle between its positions.

The resilient urging of the retainer slide toward the cam engagement with the auxiliary locking slide has usually been accomplished by some'form of leaf-type spring, either a continuous arcuate leaf or one having an intermediate loop for additional resiliency, in either case, the free ends of the leaf-type spring being engaged with the retainer housing and a mid portion of said spring engaged by the retainer slide. Such leaf-type retainer slide springs have caused some difficulties due to the problems 3,390,910 Patented July 2, 1968 of retaining such leaf-type springs properly positioned within the retainer housings while still providing the retainer slides properly engaged therewith and with sufficient resilient force thereagainst to provide proper movement of such retainer slides. The improvements of the present invention are primarily concerned with such retainer slide spring arrangement and the mounting thereof in the retainer housing.

Furthermore, in latch and latch control devices of the foregoing character, the latches are normally resiliently urged toward extended position, that is, engaging the strikes when the doors are closed. Such resilient urging of the latches toward extended positions, in view of the operable connection of the latches with the main operating spindles, normally also serves to return the doorknobs to a neutral position and retain them in said neutral position through said resilient urging. There are many occasions where the springs associated with the latches and providing this resilient urging for both the latches and the doorknobs cannot be provided of sufficient size and resilient strength to properly accomplish such action, thereby not properly functioning for the intended purpose.

Additionally, it is desirable that the doorknobs will be relatively firmly retained in the neutral position during the aforesaid locking and unlocking of the latch control devices. Whether the latch control devices are unlocked from the interior doorknob by pivoting the button relative to said interior doorknob to move the locking spindle or by turning the lock with a key relative to the exterior doorknob to move the locking spindle, the inadequancy of the latch springs to firmly retain the doorknobs in their neutral positions has resulted in the necessity of retaining the doorknobs with one hand while manipulating the interior button or exterior lock with the other hand. Even under this two-handed operation, the proper locking or unlocking of the latch control devices can be relatively difficult.

It is, therefore, an object of my invention to provide a latch control device having a unique spring arrangement therein for resiliently urging the retainer slide thereof toward the auxiliary locking spindle retaining position, which spring arrangement is much more positive than has been possible heretofore and which eliminates the mounting difliculties for the required springs. A retainer slide spring is provided which is a coil spring having at least one complete turn, and preferably at least one and one-half turns, said coil spring being peripherally engaged by tabs depending from the retainer housing, and also being peripherally engaged by a portion of the retainer slide, preferably a tab depending from said slide. Such spring constantly resiliently urges the retainer slide into its auxiliary locking spindle retaining positions while, at the same time, squashing or radially inwardly circumferentially deforming to permit the slidable movement of the retainer slide for the movement of said auxiliary locking spindle between the positions thereof.

It is a further object of my invention to provide a latch control device of the foregoing type in which said coil spring has substantially diametrically oppositely depending ends engaging the stationary frame of the latch control device wherein said coil spring will not only provide the foregoing retainer slide control and the required resilient urging thereof, but will also provide resilient urging for the doorknobs to return said doorknobs to neutral latch extended positions. Such provides additional resilient force tending to retain the doorknobs in their neutral positions and resisting rotation thereof during either interior or exterior unlocking of the latch control device, as previously. discussed. Thus, the coil spring provides the dual function of retainer slide control and self-aligning or neu- 3 tral positioning knob control supplementing the previously discussed knob control by the latch springs.

It is still another object of my invention to provide a latch control device wherein the unique coil spring arrangement may be provided for serving solely as the knob selfaligning means and in the same manner as previously discussed, in which case, the locking mechanism for the latch control device is eliminated and said latch control device is nonlocking. With such arrangement, a single standard model of latch and latch control assembly may be provided with which the choice of a locking or unlocking latch control device may be offered with only minor alterations in the various parts thereof so that the latch portion of the parts for the assembly may be standard regardless of the choice, with only a few of the parts being specifically formed for the particular form. Such standardizing feature promotes economics in manufacture and reductions in selling costs.

Other objects and advantages of the invention will be apparent from the following specification and the accompanying drawings which are for the purpose of illustration only, and in which:

FIG. 1 is a top plan view of a latch and latch control assembly incorporating the principles of the present invention and mounted in association with a door and doorframe, said door and doorframe being shown in horizontal section;

FIG. 2 is an enlarged, vertical, sectional view taken along the broken line 22 in FIG. 1 and showing the latch control device in locked position;

FIG. 3 is a vertical, sectional View taken along the broken line 3-3 in FIG. 2;

FIG. 4 is an enlarged, fragmentary, vertical, sectional view taken along the broken line 44 in FIG. 2;

FIG. 5 is an enlarged, fragmentary, vertical, sectional view taken along the broken line 5-5 in FIG. 2;

FIG. 6 is an enlarged, fragmentary, vertical, sectional view taken along the broken line 66 in FIG. 2;

FIG. 7 is a fragmentary, horizontal, sectional view taken along the broken line 77 in FIG. 6;

FIG. 8 is a view similar to FIG. 5, but showing the latch control device in the unlocked position;

FIG. 9 is a view similar to FIG. 8, but additionally showing the retainer slide coil spring, said spring being a modified form providing the single function of controlling retainer slide movement without the knob self-aligning feature; and

FIG. 10 is a view similar to FIG. 9 showing the latch control device modified to eliminate the locking feature thereof, but the coil spring arranged to provide the knob self-aligning feature thereof.

Referring to FIGS. 1 through 7 of the drawings, the latch and latch control assembly illustrated and incorporating the principles of the present invention includes a latch control unit generally indicated at and a latch unit generally indicated at 22, said control and latch units being assembled for actuation of the latch by the latch control unit and arranged for mounting in a door 24 cooperable between said door and a doorframe 26. As shown particularly in FIG. 1, the latch control unit 20 includes usual interior and exterior doorknobs 28 and 30 rotatably mounted on a stationary frame 32 formed by rosette plates 34 and 36 axially connected through the door 24 by studs 38, said doorknobs 28 and 30 being connected for rotating an axially extending main latch spindle 40 connecting said knobs through the door 24. The main latch spindle 40 is the usual half-round spindle and is engaged axially through the latch unit 22 within the door 24 for withdrawing a latch member 42 of the latch unit from engagement with a strike 44 mounted on the doorframe 26 upon rotation of the doorknobs 28 and 30 and the main latch spindle 40.

A spindle retainer assembly generally indicated at 46 is secured on the main latch spindle 40 for rotation therewith and is located axially telescoped by the exterior rosette plate 36 and axially inward of the exterior doorknob 30. Said spindle retainer assembly 46 includes a housing 48 press-fit axially telescoping the main latch spindle 40 and axially enclosing a radially slidable locking slide or member 50. The locking member 50 is guided for said radial slidable movement within and from the housing 48 by opposite housing sides 52, with the locking member being bifurcated at one edge to form a locking recess 54 engageable with one of the stationary frame studs 38 when the locking member is in extended position projecting radially from the housing 48, as best seen in FIGS. 4, 5 and 6, said locking recess being disengaged from said stud when the locking member is in a retracted position slid radially into the housing 48, as shown in FIG. 8.

Thus, the extended position of the locking member 50 is a locking position in which the engagement between the locking member and the stationary frame stud 38 retains the locking member and through the locking member, the retainer assembly housing 48, the main latch spindle 40 and the doorknobs 28 and 30 against rotation so that the latch unit 22 cannot be actuated thereby. Furthermore, the retracted position of the locking member 50 in which said locking member is disengaged from the stationary frame stud 38 constitutes a nonlocking position wherein rotation of the main latch spindle 40 and the doorknobs 28 and 30 is permitted to actuate the latch unit 22.

An edge of the locking member 50 radially opposed to the locking recess 54 is formed with a cam recess 56 having an angled cam surface 58, cam slot 60 and a cam projection 62. An auxiliary locking spindle 64 is received within the channeled contour of the half-round main latch spindle 40 extending co-axially therewith, said auxiliary locking spindle being rotatable o'r circumferentially pivotal relative to the main latch spindle and having an integral guide lug 66 juxtaposed axially outwardly of the retainer housing 48. For controlling movement of the locking member 50, the auxiliary locking spindle 64 is formed with an integral locking cam 68 axially within the retainer housing 48 and radially aligned with the locking member 50 within the locking recess 54.

The auxiliary locking spindle 64 is received rotatable through the stationary frame rosette plates 34 and 36 and the doorknobs 28 and 30 within the main latch spindle 40, with an interior end 70 keyed to a locking button 72 at the interior doorknob 28 and an exterior end 74 engaged with a cylinder lock 76 at the exterior doorknob 30. Thus, by manipulating either the interior knob locking button 72 or the exterior knob cylinder lock 76 to rotate or pivot the auxiliary locking spindle 64 relative to the doorknobs 28 and 30 and the main latch spindle 40, the locking cam 68 will pivot within the locking member cam recess 56 to move the locking member 50 between the previously described locking and nonlocking positions. As best seen in FIG. 5, the locking cam 68 bears against the angled cam surface 58 of the locking member 50 to force the locking member radially into locking position engaged with the stationary frame stud 38, and as shown in FIG. 8, pivotal movement of the locking cam 68 along the angled cam surface 58 into the cam slot 60 of the locking member engages the locking cam with the cam projection 62 of the locking member, forcing the locking member radially inwardly relative to the stationary frame stud 38 to disengage the locking member therefrom and place the locking member in the nonlocking position.

A retainer slide or member 78 is also received within the retainer housing 48 axially spaced from the locking member 50 and guided for radial slidable movement relative to said housing between the housing sides 52, as best seen in FIGS. 6 and 7. Said retainer member 78 is formed with an interior opening 80 forming a cam follower lobe 82 separating cam dwell. portions 84 and 86, said cam follower lobe 82 being at the side of the retainer member opening and radially aligned with the locking recess 54 of the locking member 50. Radially opposite the cam follower lobe 82, the retainer member 78 is formed with an axially extending tab 88 projecting axially toward but spaced from, the locking member 50, for an important purpose to be hereinafter described.

A retainer cam 90 is formed integrally on the auxiliary locking spindle 64 projecting radially therefrom radially aligned for engagement with the retainer member 78 within the retainer member interior opening 80, said retainer cam being axially aligned on the auxiliary locking spindle with the locking member locking cam 68. The retainer cam 90' is normally received within one or the other of the cam dwell portions 84 and 86 of the retainer member 78, but upon selective pivotal movement of the auxiliary locking spindle 64 relative to the main latch spindle 40, the retainer cam is movable over the cam follower lobe 82 of the retainer member to force the retainer member radially slidably relative to the auxiliary locking spindle and the retainer housing 48. .When the locking cam 68 is in the locking position forcing the locking member 50 to locking position, as shown in FIG. 5, the retainercam 90 is received in the cam dwell portion 86, as shown in FIG. 6, and when the locking cam 68 is in nonlocking position withdrawing and placing the locking member 50 in nonlocking position, as shown in FIG. 8,-the retainer cam 90 is received in the cam dwell portion 84 of the retainer member 78, with the movement of the retainer cam 90 over the cam follower lobe 82 of the retainer member 78 being the period of movement of the locking cam 68 between such locking and nonlocking positions.

Most important to the improvements of the present invention, a coil retainer spring 92 is positioned within theretainer housing 48 axially between the locking member 50 and the retainer member 78 spaced radially outwardly from and circumferentially surrounding the main latch spindle 40 and the auxiliary locking spindle 64. The coil retainer spring 92 includes at least one complete circumferentially extending coil, and preferably at least an.additional substantially one-half coil, terminating in generally diametrically oppositely depending ends 94 oppositely circumferentially engaged with the retainer housing sides 52 and extending generally radially outwardly beyond the retainer housing 48 and oppositely circumferentially engaging stationary frame lugs 96 extending axially from the stationary frame exterior rosette plate 36, as best seen in FIGS. 2, 4 and 6. The previously described axially extending tab 88 'of the retainer member 78 peripherally and radially engages the coil retainer spring 92, with an opposite side of the coil retainer spring generally radially oppositethe retainer member tab 88 being peripherally and radially engaged by spaced spring positioning tabs 98 extending axially from the retainer housing 48, said spring positioning tabs beingradially outward of the retainer member 78 and permitting the slidable movement of said retainer member within the retainer housing.

The coil retainer spring 92 is positioned between the retainer member tab 88 and the housing spring positioning tabs 98 slightly circumferentially or radially inwardly deformed at all times to constantly resiliently urge the retainer member 78 radially toward the retainer cam 90 of the auxiliary locking spindle 64 so that the coil retainer spring normally resiliently urges the retainer cam of the auxiliary locking spindle intoone of the retainer member cam dwell portions 84 or 86. Further circumferential or radially inward deformation of the coil retainer spring 92, however, will permit the retainer member 78 to slide radially as radially forced by the retainer cam 90 of the auxiliary locking spindle 64 sliding over the retainer member cam follower lobe 82. The unique arrangement of the retainer member 78 and the coil retainer spring 92, therefore, resiliently retains the auxiliary locking spindle 64 in one of the locking memher locking or nonlocking positions, while permitting pivotal movement of the auxiliary locking spindle 64 relative to the main latch spindle 40 between said locking and nonlocking positions by circumferential deformation of the coil retainer spring, as described.

In view of the fact that the coil retainer spring ends 94 engage generally radially outwardly with the stationary frame lugs 96, as also described, the coil retainer spring 92 performs the dual function of not only resiliently retaining the auxiliary locking spindle 6'4 and the locking member 50' in one of the locking or non-locking positions while permitting movement therebetween, but also resiliently resisting rotation of the main latch spindle 40 and the interior and exterior doorknobs 28 and 30 secured thereto so as to always resiliently urge from either direction of rotation the doorknobs to return to a neutral or center position in which the latch member 42 of the latch unit 22 is extended. Such resilient force of the coil retainer spring 92 resiliently resisting the rotation of the doorknobs 28 and 30 is in addition to any resilient urging by the latch member 42 of the latch unit 22 attempting to move to extended position and thereby provides what might be termed a self-aligning latch and latch control assembly. Furthermore, such antirotation or self-aligning feature for the doorknobs 28 and 30 will provide a much greater resilient force tending to retain the doorknobs stationary during manipulation of either the locking button 72 at the interior doorknob 28, or the cylinder lock 76 at the exterior doorknob 30 for locking or unlocking the latch control unit 20, making it unnecessary to retain the doorknobs with one hand while performing such manipulation with the other, as was required in most prior constructions.

As shown in FIG. 9, where it is not desired to provide the self-aligning feature, it is merely necessary to provide a coil retainer spring 108 having shortened spring ends 102 which merely engage retainer housing sides 104 and do not extend radially to engage any portion of stationary frame '106. Otherwise, the positioning and function of the coil retainer spring is the same as previously described.

As shown in FIG. 10, Where the self-aligning or antirotation feature is desired, but it is not desired to provide locking of a main latch spindle 108, the locking mechanism is eliminated, while coil retainer spring remains the same, with spring ends 112 extending radially engaging both retainer housing sides 114 and stationary frame lugs 116. In this modified form, the coil retainer spring 110 will still resiliently resist rotation of the main latch spindle '108 to provide the self-aligning function for the coil retainer spring 110.

According to the present invention, therefore, I have provided a unique coil spring arrangement in a latch control device which may be constructed to perform the dual function of locking or unlocking retainment and doorknob self-alignment. Furthermore, the locking or unlocking retainment, and the movement therebetween, is accomplished by a coil retainer spring being circumferentially deformed through peripheral and radially inward force thereagainst. The self-alignment feature is accomplished by engaging the ends of the same coil retainer spring with the stationary frame, wherein rotation of the doorknobs from a neutral or center position in either direction of rotation will force circumferentially tighter coiling of the coil retainer spring, again circumferentially deforming the same, to resiliently resist this rotation and return the doorknobs to the neutral or centered position.

I claim:

1. In a latch control device, the combination of: latch actuator means for operating a latch including a stationary frame rotatably mounting a spindle, means connecting said spindle to said latch for operating said latch upon rotation of said spindle, latch operating means for selectively rotating said spindle; and a spindle retainer assembly including a housing secured to said actuator spindle rotatable therewith, a locking member on said housing movable between an extended locking position engaging said stationary frame and locking said actuator spindle against rotation and a retracted nonlocking position disengaged from said stationary frame and permitting rotation of said actuator spindle, positioning means selectively operable for moving said locking member between said extended and retracted positions, retainer means radially slidable between positions retaining said locking member in each of said extended and retracted positions and permitting movement of said locking member between said extended and retracted positions, a coil retainer spring on said housing having at least one complete circumferentially extending coil, engagement means on said retainer means peripherally engaged with said retainer spring coil for said coil to normally resiliently resist said retractor means slidable movement and for radially inwardly and circumferentially deforming said coil upon slidable movement of said retainer means to permit said locking member movement between said extended and retracted positions.

2. A latch control device as defined in claim 1 in which said retainer spring coil circumferentially surrounds said actuator spindle.

3. A latch control device as defined in claim 1 in which said retainer spring coil circumferentially surrounds said actuator spindle; and in which said housing includes spaced tabs peripherally engaging said retainer spring coil at circumferentially spaced locations and generally radially opposed to said engagement means peripheral engagement of said retainer spring coil.

4. A latch control device as defined in claim 1 in which said retainer spring coil circumferentially surrounds said actuator spindle and extends at least substantially one and one-half turns terminating in generally diametrically oppositely depending ends engaged with said housing.

5. A latch control device as defined in claim 1 in which said retainer spring coil circumferentially surrounds said actuator spindle and extends at least substantially one and one-half turns terminating in generally diametrically oppositely depending ends engaged with said housing; and in which said housing includes spaced tabs peripherally engaging said retainer spring coil at circumferentially spaced locations and generally radially opposing said engagement means peripheral engagement of said retainer spring coil.

6. A latch control device :as defined in claim 1 in which said retainer spring coil circumferentially surrounds said actuator spindle and extends at least substantially one and one-half turns terminating in generally diametrically oppositely depending ends engaged with said stationary frame, said retainer spring coil through said coil end engagement with said stationary frame resiliently resisting rotation of said spindle and housing relative to said stationary frame in either direction of rotation.

7. A latch control device as defined in claim 1 in which said retainer spring coil circumferentially surrounds said actuator spindle and extends at least substantially one and one-half turns terminating in generally diametrically oppositely depending ends engaged with said stationary frame, said retainer spring coil through said coil end engagement with said stationary frame resiliently resisting rotation of said spindle and housing relative to said stationary frame in either direction of rotation; and in which said housing includes spaced tabs peripherally engaging said retainer spring coil at circumferentially spaced locations and generally radially opposed to said engagement means peripheral engagement of said retainer spring coil.

8. In a latch control device of the type having a stationary frame rotatably mounting a spindle operably connected to a latch for operating said latch upon rotation of said spindle, latch operating means for selectively rotating said spindle, a housing secured to said spindle rotatable therewith, a locking member on saidhousing movable between an extended locking position engaging said stationary frame and locking said spindle against rotation and aretracted nonlocking position disengaged from said stationary frame and permitting rotation of said spindle, positioning means selectively operable for moving said locking member between said extended and retracted positions, retainer means radially slidable between positions retaining said locking member in each of said extended and retracted positions and permitting movement of said locking member between said extended and 'retracted positions; the improvements including,-a. coilretainer spring on said housing having at least one complete circumferentially extending coil, engagement means on said retainer means peripherally engaged with said-retainer spring coil for said coil to normally resiliently resist said retainer means slidable movement and for radial inward and circumferential deformation of said coil upon slidable movement of said retainer means to permit said locking member movement between said extended and retracted positions.

9. A latch control device as defined in claim 8 in which said retainer spring coil circumferentiallysurrounds said spindle; and in which said housing includes spaced-tabs peripherally engaging said retainer spring coil at circumferentially spaced locations and generally radially opposing said engagement means peripheral engagement of said retainer spring coil.

10. A latch control device as defined in claim 8 in which said retainer spring coil circumferentially surrounds said spindle and extends at least substantially one and one-half turns terminating in generally diametrically oppositely depending ends engaged with said housing.

11. A latch control device as defined in claim Sin which said retainer spring coil circumferentially surrounds said spindle and extends at least substantially one and one-half turns terminating in generally diametrically oppositely depending ends engaged with said housing; and in which said housing includes spaced tabs peripherally engaging said retainer spring coil at circumferentially spaced locations and generally radially opposed to said engagement means peripheral engagement of said retainer spring coil. 7

12. A latch control device as defined in claim 8 in which said retainer spring coil circumferentially surrounds said spindle and extends at least substantially one and one-half turns terminating in generally diametricallyoppositely depending ends engaged with said stationary frame, said coil ends resiliently resisting rotation of said spindle and housing relative to said stationary frame. r

13. A latch control device as defined in claim 8 in which said retainer spring coil circumferentially surrounds said spindle and extends at least substantially one and one-half turns terminating in generally diametrically oppositely depending ends engaged with said stationary frame, said coil ends resiliently resisting rotation of said spindle and housing relative to said stationary frame; and in which said housing includes spaced tabs peripherally engaging said retainer spring coil at circumferentially spaced locations and generally radially opposing said engagement means peripheral engagement of said retainer spring coil. s

References Cited UNITED STATES PATENTS 2,985,478 5/1961 Russell 292-3363 2,998,273 8/1961 Unetic 292-359, K 3,075,796 1/1963 iRussell 292 ,3 3'6.3 MARVIN 1A. CHAMPION, Primary Examiner.

EDWARD J.'MCCA-RTHY, Assistant Examiner. 

1. IN A LATCH CONTROL DEVICE, THE COMBINATION OF: LATCH ACTUATOR MEANS FOR OPERATING A LATCH INCLUDING A STATIONARY FRAME ROTATABLY MOUNTING A SPINDLE, MEANS CONNECTING SAID SPINDLE TO SAID LATCH FOR OPERATING SAID LATCH UPON ROTATION OF SAID SPINDLE, LATCH OPERATING MEANS FOR SELECTIVELY ROTATING SAID SPINDLE; AND A SPINDLE RETAINER ASSEMBLY INCLUDING A HOUSING SECURED TO SAID ACTUATOR SPINDLE ROTATABLE THEREWITH, A LOCKING MEMBER ON SAID HOUSING MOVABLE BETWEEN AN EXTENDED LOCKING POSITION ENGAGING SAID STATIONARY FRAME AND LOCKING SAID ACTUATOR SPINDLE AGAINST ROTATION AND A RETRACTED NONLOCKING POSITION DISENGAGED FROM SAID STATIONARY FRAME AND PERMITTING ROTATION OF SAID ACTUATOR SPINDLE, POSITIONING MEANS SELECTIVELY OPERABLE FOR MOVING SAID LOCKING MEMBER BETWEEN SAID EXTENDED AND RETRACTED POSITIONS, RETAINER MEANS RADIALLY SLIDABLE BETWEEN POSITIONS RETAINING SAID LOCKING MEMBER IN EACH OF SAID EXTENDED AND RETRACTED POSITIONS AND PERMITTING MOVEMENT OF SAID LOCKING MEMBER BETWEEN SAID EXTENDED AND RETRACTED POSITIONS, A COIL RETAINER SPRING ON SAID HOUSING HAVING AT LEAST ONE COMPLETE CIRCUMFERENTIALLY EXTENDING COIL, ENGAGEMENT MEANS ON SAID RETAINER MEANS PERIPHERALLY ENGAGED WITH SAID RETAINER SPRING COIL FOR SAID COIL TO NORMALLY RESILIENTLY RESIST SAID RETRACTOR MEANS SLIDABLE MOVEMENT AND FOR RADIALLY INWARDLY AND CIRCUMFERENTIALLY DEFORMING SAID COIL UPON SLIDABLE MOVEMENT OF SAID RETAINER MEANS TO PERMIT SAID LOCKING MEMBER MOVEMENT BETWEEN SAID EXTENDED AND RETRACTED POSITIONS. 